Railway signaling system



A1182 13, 1940 F. H. RICHTERKEsslNG A 2,211,579

RAILWAY SIGNALING SYSTEM Original Filed June 25, 1957 tPatented Aug. 13,1940 UNITED STATE PATENT OFFICE RAILWAY SIGNALING SYSTEM porated,Louisville, Ky,

Kentucky a corporation of Application 'June 25, 1937, Serial No. 150,237Renewed November 22, 1939 18 Claims.

My invention relates to a system of signaling adapted to govern car ortrain movements on an electric or other railway, and more particularlyto a railway having a single track section equipped with a plurality ofturnouts or sidings.

The principal application of my invention resides in the signaling of amain line haulage of a mine employing a single track railway connectingthe various working sections of the mine by a plurality of branch tracksections.

My invention embraces a system of and apparatus for electric signaling,in which the signal control apparatus for each signal station of thesignaled section is entirely symmetrical; the complete signaled sectionbeing made up of duplicate control apparatuses for each entry desired tobe protected and operatively connected through tWo line wires.

My invention resides in a signaling system in which any number of signalstations may be added to an existing signaled section by merely addingsimilar parts for each additional signal station Without increasing thenumber of controlling line wires.

My invention also embraces a signaling system in which only one proceedsignal is displayed under conditions of simultaneous entrance,regardless of the number of vehicles involved in the simultaneousmovement.

00 My invention resides further in a signaling system which, once setinto operation by a vehicle entering the signaled section, can not bechanged by the entrance of other cars into the signaled section, untilthe vehicle for which the signaling 3- protection was established passesout of 'the signaled section.

My invention resides further in the providing of a signaling system inwhich an open in either of the signal controlling line Wires Will eect afailure on the safe side, that is, an open in the signal controllingline wire, which is often encountered in mines by the breaking of a lineWire due to falling slate, roof cave-ins, etc., will automatically setall signals at red and prevent any further change in the display of thesignals until such conditions are corrected. The opening of therestoring line wirewill automatically set one or more of the signals atred, dependent upon the location of the break in the line Wire, andsimilarly prevent restoration of the signals to normal until the faultis corrected.

My invention resides further ina signaling system that is primarilyintended for use with those vehicles collecting propulsion current froma trol- 55 ley Wire by trolley Wheels or shoes, and in Which (Cl. 24S-128) the control of the signals is activated by trolley contactorsengaged during the movement of the current collectors on the trolleywire.

My invention further resides in the locating of the trolley contactorsat each signal station, 5y such that separate locations are employed forthe respective setting and restoring trolley contactors, therebypreventing the restoration of the signals to normal by a vehiclereversing its movement at the setting contactor location. m

My invention still further resides in the arranging of the signalcontrol circuits, such that the source of current for operating thecontrols governing the proceed indication, is obtained from only onesignal station hereinafter referred lo to as the principal signalstation.

My invention further resides in the arrangement of the signal circuits,wherein, under conditions of simultaneous entrance of vehicles into thesignaled section, the controls will definitely 20 establish a proceedindication at the signal `station nearest the principal station. 'Iheobject of such an arrangement being to favor the movement of a vehicleoperating with either a heavy load or requiring to climb a grade. Suchfavoring 25 in the vehicle control of the signals may be utilized toother advantages, such as the elimination of rapid braking on steepgrades, retarded main line movements, etc.

My invention further resides in the inclusion of a dispatcher control inthe signal system Without additional line wires, ,such control enablinga dispatcher to hold or set all signals at red and prevent a train fromentering the signaled section, for such emergencies as cave-ins, trackdamages, broken trolley Wire, derailed train, etc.

It willl be further obvious to those skilled in the art that, by reasonof the novelty and originality of my signal system, there are many otherobjects that Will become apparent as the speci- 0 cation is read inconnections with the accompanying drawing. For an illustration of oneembodiment of my invention, reference is made to the accompanyingdrawing, in Whichy Figure l is a diagrammatic representation of thecircuits and apparatus illustrating one form of my invention.

Fig. 2 is a fragmentary diagrammatic illustration of a directional relaysystem that may besubstituted for the mechanical trolley contactors Sland Nl employed in Fig. 1. Fig. 3 is a diagrammatic illustration of thecircuits and apparatus of another form of directional controlillustrated in Fig. 2.

Referringto Fig. l, the conductor or trolley wire T represents a feedersupplying operating current to both the signaling system and thevehicles operating on the section of the railway system, while, as isWell understood in the art, the return conductor for the current iseither the earth y, track rails a: or both as conditions may require.

As hereinbefore expressed, the major object of my invention is toprovide a signaling system, for a section of railway track consisting ofa plurality of entries into a main track section, in which each entryconstitutes a signal station and wherein any desired number of stationsmay be connected to form a unitarily controlled signal section. Sincethree stations may be conveniently employed to illustrate the operationof such a signaling system, Fig. 1 diagrammatically illustrates suchembodiment.

In Fig. l the section of railway extending between stations I and 3 maybe regarded as the main track section, and it is to be noted that oneend of the main track section at station 3 is illustrated as comprisinga passing siding, while the other end at station I is represented asforming a continuation of the single track. It will be further notedthat the above referred to main track section is joined by a singletrack turnout, which will be hereinafter identified as signal station 2.

Although the accompanying drawing illustrates my invention as applied toan electric railway, wherein the signal controlling apparatus isactuated by a suitable form of trolley contactor, I do not desire tolimit my invention to this particular application, since the principlesembodied in my invention are readily applicable to signaling systems inwhich the control may be responsive to the operation of photo electricdevices, magnetic inductors, track instruments, track circuits, or anyother form of control that will retain the relay system active as longas a vehicle occupies the section of railway between the various signalstations.

In the embodiment of my invention, illustrated in Fig. l, each signalstation is provided with Vehicle controlled contact mechanisms whereby amember, such as a traveling contact or trolley wheel carried by a movingcar or train, causes closure of signal control circuits. These vehiclecontrolled contact mechanisms may comprise suitable mechanically movablecontact members, indicated at station I as NI and SI respectively, thatare deflectable in opposite directions by the trolley wheel or someother member carried by the car or train, according to the direction oftravel of the car or train.

At signal station I the movable contact member NI is provided with astationary contact 33, which, as indicated by the arrow, is engaged bythe contact member NI only when the car leaves the signaled section. Itwill be further noted that the movable contact member SI is providedwith a stationary contact I, which, as indicated by the direction of thearrow adjacent member SI, is engaged by the member SI only when a trainis entering the signaled section.

While this simple mechanical type of directional sensitive vehiclecontrolled mechanism is described, it is to be understood that any othersuitable directional-sensitive circuit controlling mechanism may beemployed. Such circuit controlling mechanisms are in partdiagrammatically illustrated in Figs. 2 and 3, which will be hereinafterdescribed in detail.

The signal indications of the system are diagrammatically illustrated assignal lamps. ever, it is to be understood that any suitable form ofsignaling means may be substituted for such signal lamps.

The signal lamps are adapted to convey to the operator of a vehicle thecondition of the signaled territory, that is, whether same is occupiedby train movements, and the direction in which such movements are beingmade. It is to be further understood that these signal lamps areprovided with suitable colored roundels to distinguish the indications.In the embodiment illustrated, I have employed red roundels for lampsRI, R2 and R3 to denote Stop, and green roundels for lamps GI, G2 and G3to indicate Proceed. A similar red roundel is provided for signal lampR.

In Fig. 1 similar relays are employed at each signal station. At stationI these relays are,

namely; a neutral relay MI and a mechanical interlocking relay CI-AI. Itwill be well to note that the similar relays at each signal stationtogether with all other similar apparatuses are designated by similarcharacters. For instance, the neutral relay in station I is designatedas MI, While the neutral relay in station 3 is designated as M3, etc.

The operation of the mechanical interlocking relay AI-CI is very simple.The relay consists of twoneutral relays positioned side by side with amechanical latch member XI arranged to be engaged by the armatures ofthe respective neutral relays. When the armature BI of relay CI isattracted, the latch member XI is moved out of the path of the armatureDI of the neutral relay AI, thereby permitting the armature DI of relayAI to remain in its unattracted position so long as the operating coilof relay AI remains de-energized. When the operating coil of relay CI isde-energized and its armature BI releases, the mechanical latch XI willmove into the path of armature DI of relay AI. It will be evident,therefore, that when the operating coil of relay AI is momentarilyenergized, the armature DI of relay AI will be mechanically locked inits actuated condition regardless of the condition of the operating coilof relay AI after such operation. Also, when the armature BI of relay CIis subsequently attracted to its operated position, the latch XI will bemoved out of the path of armature DI, thereby permitting the armature DIto restore to its normal condition.

Before proceeding with the detailed description of the operation of Fig.1, it is believed that notation should be made of the normal conditionof the relays and signals in my system. Normally, with no trainsoccupying the signaled section, all signals are held at dark, andneutral relays MI, M2 and M3 are retained de-energized. Similarly, theoperating coils of relays AI, A2 and A3 are de-energized. However, it iswell to note that the operating coils of relays CI, C2 and C3 arenormally energized holding their respective armatures normally in anactuated condition. Observing the circuits of station I, it will benoted that the armature BI normally engages its front contact 4 anddisengages its back contact II, thereby normally connecting theoperating coil of relay AI to the earth or negative return of thecurrent supply, and opening the circuit of the signal lamps GI and RI.Thus as long as the operating coils of the C relays of each signalstation are retained energized, the signals are held dark and theoperating coils of the A relay are held in condition to be energized inresponse to Howthe entrance of a vehicle into the signaled section.However, when the operating coils of the C relays are de-energized, theoperating coils of the A relays are withheld from energization, and acircuit is completed at each signal station to one or other of therespective signal lamps, dependent upon the selection determined by therespective M relay. From the foregoing it will be obvious thatregardless of the manner in which the operating coils of the C relays-are de-energized, whether due to an open coil, a short circuited coil,faulty ground connection, broken line wire, etc., the operating magnetsof the A relays will be locked out, that is, withheld from operation,and the local circuit to the signal lamps at each station completed.

Two line wires interconnect the signal stations of the complete signaledsection. Line wires 2i! and 29 interconnect stations l and 2 while linewires 22--22a and 26 interconnect stations 2 and 3. If it is desired tohave another station located between stations i and 2 no additional linewiring would be required. The extra station would merely connect to theexisting line wires 2Q and 29. Similarly any number of stations could beadded between stations 2 and 3 for instance by merely connecting to theexisting line wires 22- 22a and 26. If it is desired to include a signalstation remote from the section presently signaled, it would benecessary to run two line Wires to the nearest point of the signaledsection.

The dispatcher control of Fig. 1 consists of a normally closed switchinserted in the signal controlling line wire 2i) o1' 22-22a. Any numberof these switches may be inserted in either of these line wires atpoints convenient to the dispatcher. These switches may be of anydesired construction but preferably a rotary snap switch of theindicating type. The character D illustrates such a snap switchinstalled in the signal line wire 22-22a. At times it is desirable tocause the stop signal at one station to be continuously active toprevent trains 'entering the signaled section at this point. Thisindependent control of the signal is accomplished by opening the circuitof the operating coil of the C relay at the sta-- tion where the stopsignal is to display. If it is desired to cause the stop signal Rl atstation l to be continuously illuminated, wire 21 is `disconnectedthereby opening the circuit of the operating coil of relay Cl. .Thisde-energization of the operating coil of relay CI will cause armature Blto open the circuit of the operating coil of relay Ai and complete thecircuit of signal Rl. Similarly wires 6l or 25 of stations 2 and 3 maybe disconnected. It is to be noted that this control of the signal'atstation l in no way affects the operation of the signals at stations 2and 3. Car or train operations at stations 2 and 3 may continue in anormal manner unaware of the condition of station i. In this way ifcongestion has occurred on any one oi the routes the signals may becontrolled by opening the circuit of the operating coil of therespective C relay, and permit uninterrupted movement of the cars ortrains between the other stations. It is likewise important to note thatwhen the dispatcher switch D is opened, all signals will simultaneouslydisplay their stop indication, which condition can not be changed byeither` the entrance of a car into the signaled section or by a carleaving the signaled section. The signals will therefore continue todisplay their restricted indication until the dispatcher switch isrestored toits normal condition.

Vehicle operation of Figure. 1

With no car or train in the signaled section, all signals are held in anormal-dark condition. The control eiecting this condition of thesignals is the circuit normally retaining the C relays energized. InFig. 1 this circuit' is established from the positive conductor T atstation I, through wire ii, armature Di of relay Ai, contact IS, linewire 2d, armature D2 of relay A2 at station 2, contact 2i, line wire 22,snap switch D, wire 22a, armature D3 of relay A3 at station 3, contact23, jumper wire 24, wire 25, operating coil of relay C3, through wire l0to the ground return. It will be further noted that the operating coilof relay Ci is likewise connected to receive positive potential fromjumper wire 24, through wires 26 and 21 the operating coil of relay vCibeing connected to the ground return through wire 2S. Similarly, theoperating coil of relay C2 is connected to receive positive potentialfrom jumper wire 2d through wires 26, 29 and 6l the operating coil ofrelay C2 being connected to the ground return through wire 3b. Thelatter mentioned 'circuit from jumper wire 24 merely establishes a iiowof energization current from the signal line wire 2ii-22-22a, whichincludes an armature and back contact of the respective A relays at eachsignal station, through the jumper 2c to the restoringline wire 25-29which normally connects the operating coils of the respective C relaysof each signal station in a multiple circuit. This circuit for retainingthe operating coils of the C relays normally energized may be regardedas a stick or retaining circuit. With further reference to Fig. 1 itwill be noted that the restoring line wire 12S-29 is connected toreceive an initial energizing impulse from one of the restoringcontactors N. At station I it will be noted that the restoring contactorNl connects the restoring line wire 25-29 through contact 33. At station2 the restoring contactor N2 connects the restoring line wire 29-26through wire Si and contact 32. At station 3 the restoring contactor N3is connected to the restoring line wire 26-23 through contact 31E. Itwill be apparent that an operation of either of the N restoringcontactors will momentarily connect the operating coil of eachrespective C relay to the positive conductor T. This operation of the Crelays will condition the signal circuits so that the retaining circuitwill be immediately established from wire t at station i, through thesignal line wire 20-22--22a, and jumper wire 2li.

Assuming that a vehicle is entering at station l,

the engagement of its trolley wheel with the restoring contactor Nl willhave no effect on the operation of the system. However, when the trolleywheel of the entering vehicle engages the setting contactor S l acircuit is completed from the positive conductor T through member Si,contact l, wire 2, operating coil of relay Ai, wire 3, contact Il,armature Bi of relay Ci, Wire 5 to the ground return. This energizationof the operating coil of relay Ai will cause the armature DI of relay Aito disengage its back contact i9 and to be brought into engagementwithits front contact l. This disengagement of back contact i 9 removesjumper wire 2 :from positive potential, thereby deenergizing theoperating coils of the C relays at each respective signal station, andcausing their respective armatures to release from their operatedcondition. When armature Bl of relay CI releases, the operating circuitof relay Al is opened by the disengagement of contact 4, and

simultaneously the mechanical latch .XI moves into the path of armatureDI to mechanically retain the armature DI in its operated position.Similarly, armature B2 of relay C2 releasing, disengages its frontcontact and thereby opens the operating circuit of the coil of relay A2.Likewise, armature B3 of relay C3 releasing, disengages its front`contact and thereby opens the circuit of the operating coil of relayA3. The releasing of armatures B2 and B3 permits mechanical latches X2and X3 to move into the path of the armatures oi the A relays atstations 2 and 3. However, since these armatures are in their normalunoperated positions, no further effect will be apparent at these signalstations.

Instant to the operation of armature DI, a circuit is established forthe energization of the operating coil of relay MI, this circuit beingcompleted from the positive conductor T, through wire 6, armature DI,front contact l, wire 8, operating coil of relay MI, Wire Q to theground return. This energization of the operating coil of relay MI willcause the armature HI to disengage its back contact I3 and come intoengagement with its front contact i5.

The release of armature BI at station I also completed a circuit forenergizing the proceed signal Gi. This circuit being completed from thepositive conductor T, through Wire I8, signal lamp Gl, Wire I6, contactI5, armature HI, Wire l2, contact EI, armature BI, Wire 5 to the groundreturn. The release of armature B2 at station 2 completed a circuit forenergizing stop signal R2. The latter circuit being completed from thepositive conductor T, through Wire I3a, Wire Ila, signal lamp R2, wirelila, contact |30., armature H2, wire l2a, contact IIa, armature B2,wire 5a to the ground return. The release of the armature B3 at station3 similarly completed a circuit for energizing the stop signal R3.

In the preceding description it was assumed that a single car entered atstation I. To explain the operation of my system under simultaneousoperation it will be assumed that a car enters at station 2simultaneously With the car at station I. Under this condition ofoperation, the operating coil of relays AI and A2 will be simultaneouslyenergized. The operation of armatures DI and D2 will remove the signalclearing control wire ZF6- "9 from positive potential, and thereby causethe operating coils of relays CI, C2 and C3 to become de-energized.inasmuch as armatures DI and D2 were simultaneously operated, thede-energization of the operating coils of relays CI and C2 will permitthe mechanical latches XI and X2 to move into the path of the armaturesDI and D2 and retain them in their' operated positions. Referringparticularly to the circuits of station I, it Will be noted that theoperation of armature DI removed positive potential from armature D2 ofstation 2. Therefore, the operating coil of relay MI, at station I, willbe energized via armature DI and contact l, which will permit theenergization of the proceed signal GI. At station 2, the operating coilof relay M2 can not be energized, thereiore, the stop signal R2 Will beenergized in the same manner as described in connection with a singlecar entering at station I. Similarly, stop signal R3 at station 3 willbe energized. Thus with cars entering simultaneously at stations I and2, only the car approaching station I Will receive a proceed signal.

I will now assume that the car at station 2 operated the settingcontactor S2 slightly before the car at station I operated its settingcontactor SI. With this condition of operation it Will be apparent thatthe operating coil of relay A2 Will be energized before the operatingcoil oi relay AI. It will also be apparent that, if this time issuiicient to permit the armature BI to disengage contact 4 before theoperating coil of relay AI can operate its armature DI, the mechanicallatch X2 will retain armature D2 operated While armature DI Will remainin its unoperated position. Thus, the armature D2 being connected topositive potential T via Wire 20, contact I9, armature DI and Wire 6,will bring about the energization of the operating coil of relay M2.Therefore, the armature H2 will disengage contact I3a. and energizeproceed signal G2 through its front Contact. At station I, however,since the armature DI was not operated, the operating coil of relay MIwill not be energized. Therefore, the release of armature BI willenergize the stop signal RI through the circuit completed from thepositive conductor T, wire E8, Wire Il, stop signal RI, Wire I4, contactI3, armature HI, Wire I2, contact II, armature BI, Wire 5 to the groundreturn. Inasmuch as no car operated at station 3, the stop signal R3Will be displayed as hereinbefore mentioned.

From the foregoing it Will be apparent that in order for the proceedsignal to be displayed at a station remote from the principal stationwhere the signal control wire is connected to positive potential, itwill be necessary for the armature of the respective A relay to beoperated before the armature of an A relay nearer the principal station.Thus, according to Fig. 1 under simultaneous operation oi armatures DI,D2 and D3, station I will receive the proceed signal. Under simultaneousoperation of armatures D2 and D3, station 2 will receive the proceedsignal. However, under any circumstances if, for instance, armature D3is operated before armature DI or D2, the operating coil of relay M3Will be energized to permit the proceed signal G3 to be displayed atstation 3. Thus, the signaling is absolute in its control, and willpermit but one car to occupy the signaled section at a time.

When the car receiving the proceed signal advances and leaves the block,a restoring contactor N Will be operated to restore the signals andrelays to normal. For the purpose of illustration it will be assumedthat a car operating at station I has received the proceed signal GI andleaves the signaled territory at station 3. When the restoring contactorN3 is operated, contact 34 Will be connected to positive potential, andthe operating coils of relay CI, C2 and C3 energized. This will resultin armatures BI, B2 and B3 being restored to their normal operatedpositions. Thus the mechanical latches XI, X2 and X3 will be moved outof the path of armatures DI, D2 and D3, which will re-establish theretaining circuit for the operating coils of relays CI, C2 and C3. Thelatter circuit being completed from positive conductor T at station I,through Wire 6, armature DI, contact I9, Wire 20, armature D2, contact2I, Wire 22, twitch D, Wire 22a, armature D3, Wire 24, Wire 25,operating coil of relay C3, through Wire Ill to ground. Wire 26 beingconnected to wire 24 Will likewise energize the operating coil of relayCI via Wires 21 and 28. Similarly since wire 29 connects wire 26, theoperating coil of relay C2 Will be energized via Wires 6I and 30. It isto be noted ,that the operating coils of relays CI, C2 and C3 arearranged in a multiple circuit. Therefore, regardless or whether therestoring contactor NI N2 or N3 is operated, the coils and signals willbe restored to normal in the same manner.

At station 2 a stop signal R is provided and located to stop a carapproaching station 2 before operating the setting or restoringcontactors, whenever the signaled section is occupied. Reerring to thecircuits of station 2, it wil be noted that whenever the armature B2 oirelay C2 is released, the stop signal R is displayed. The circuit forstop signal R being completed from positive conductor T, through vwire3B, stop signal R, wire 35, contact Ha., armature B2, wire c to groundreturn. The purpose of stop signal R is to prevent cars approaching thesignaled section from passing its respective setting contactor while thesignaled section is occupied, and it is to be understood that a similar.stop signal is to be provided at stations l and 3 when this feature isrequired.

In Figs. 2 and 3 a direction-sensitive relay system is illustrated thatmay be substituted'ior the mechanical type of contactors shown inFig. 1. Referring particularly to Fig. ,2, it will be observed that twocontact strips 3l and 38 are arranged adjacent the positive conductor Tso that a trolley wheel W moving in the direction of the arrow williirst connect the contact strip 3l to the positive conductor T, thencontact strip 38. Such a relay system is described in the United StatesPatent to Frank H. Richterkessing et al. 1,915,696, issued June 27,1933. In Fig. 2 it is proposed to connect wire 4l, for instance, to wire2. Thus, the trolley wheel W moving in the direction. of the arrowconsecutively energiz- .ing the coils of relays E and F will bring thearmature L into engagement with contact 46 thereby completing a circuitfor energizing the operating coil of relay Al from the posit1veconductor T, through the current collector W, contact strip 38, wire 44,wire 45, contact 46, armature Il, wire l'l, wire 2, operating coil ofrelay Al, wire 3, contact 4, armature DI, wire 5 to the ground return.

In Fig. 3 a similar relay system is illustrated. However, this systemdoes not require the consecutive energization of the operating coils ofrelays El and Fl, but on the oother hand selective energization of same,dependent upon the consecutive engagement of the contact member 48 andllt. For illustration, assuming that the current collector W travels inthe direction of the arrow, the contact strip 48 is iirst connected tothe positive conductor T, thereby completing a circuit for energizingthe operating coil of relay Fi via wire 5t, armature K3, contact 5l,wire 53, operating coil Fl, wire 54 to ground G. When the trolley wheelW subsequently engages the contact strip 49 a circuit will be completedfor retainingT the operating coil of relay FI energized via wirearmature L3, front contact 60, operating coil of relay Fl wire 54 toground G. When .the trolley wheel moves in the direction reverse to thatindicated by the arrow, the contact strip 49 will be first connected tothe positive conductor T, thereby energizing the operating coil of relayEl via wire 55, armature L3, contact 56, wire 5l', operating coil ofrelay El, wire 58, ground G. Thus when the contact strip 43 issubsequently engaged the operating coil of relay El will be retainedenergized via wire 50, armature K3, contact 59, etc. In order to employsuch a relay system in connection with Fig. l., it is proposed that wire52 of Fig. 3 be connected to wire 2 of Fig. 1. Thus, whenever theoperating coil of relay FI is energized via contact 5I, the wire 52 willconnect the operating coil of relay Al to the positive conductor T.Having thus described my invention- I claim: v

1. A block signaling system having a plurality of signal stations, andhaving two control wires, each extending between at least two stations,the combination therewith including, a source of power at one station;normally. closed switch means at the said one station connecting oneterminal oi the said source of power to one of said control wires;normally closed switch means at the other of said stations connectingthe said one control wire to the other control wire; a relay at each ofthe said stations, each relay having a winding normally energized in acircuit including the said switches and said control wires; controlmeans at each of the said stations operable to actuate the correspondingswitch means so as to open the said circuit including the said controlwires, and to thereby de-energize the windings of the said relays; meansat each of the said stations, operated by the corresponding relay, iorretaining the corresponding switch means actuated, when the winding ofthe corresponding relay is ole-energized; a second relay at each of thesaid stations each second relay having a winding normally de-energizedand adapted to be connected to the source of power for energization,when the corresponding switch means is actuated; a proceed signal ateach of the said stations; means, controlled by the de-energization ofthe winding of a first mentioned relay and the energization of thewinding of a corresponding second mentioned relay, to operate thecorresponding proceed signal; a stop signal at each of the saidstations; and means, controlled by the de-energization of the winding ofthe iirst mentioned relay and the de-energization of the winding of thecorresponding second mentioned relay, to operate the corresponding stopsignal.

2. A block signaling system having a plurality oi signal stations, andhaving two control wires extending between at least two stations, thecombination therewith including, a source of power at one station,normally closed switch means at the said one station connecting one ofsaid control wires to one terminal of the said source of power; normallyclosed switch means at the other of said stations connecting the saidone .control wire to the other control wire; a relay at each of the saidstations, each relay having a win-ding normally energized in a circuitincluding the said switches and said control wires; control means ateach of the said stations, operable while the corresponding winding isenergized, to open the corresponding switch means to deenergize the saidwindings; means at each of the said stations, operated by thede-energization of the corresponding winding, to retain thecorrespondjing switch means open; signaling means at .each

said stations connecting the said one control wire to the other controlwire; a relay at each of the said stations, each relay having a windingnormally energized in a circuit including the said switches and the:said control wires; control means at each of the said stations,operable while the corresponding winding is energized, to actuate thecorresponding normally closed switch so as to open the said circuitincluding the said control wires, and to thereby de-energize the saidwindings; means at each of the said stations, operating when thecorresponding winding is deenergized, to retain the corresponding switchactuated; a second relay at each station, each second relay having awinding normally de-energized and adapted to be connected to the sourceof power for energization when the corresponding switch means isactuated; means, controlled by the simultaneous actuation of the saidswitches, providing energization of only one of the windings of the saidsecond relays; stop and proceed signals at each station; means, operatedby the de-energization of the winding of a rst mentioned relay and theenergization of the winding of the corresponding second mentioned relay,to operate the corresponding proceed signal; and means, operated by thede-energization of the winding of the other rst mentioned relay, tooperate the corresponding stop signal.

4. A block signaling system having a plurality of signal stations andhaving two control wires, each extending between at least two stations,the combination therewith including, a source of power at one station;normally closed switch means at the said one station connecting oneterminal of the said source of power to one of the said control wires;normally closed switch means at the other of said stations connectingthe said one control wire to the other control wire; a relay at each ofthe said stations, each relay having a winding normally energized in acircuit including the said switches and said control wires; controlmeans at each station, operable while the corresponding winding isenergized, to actuate the corresponding normally closed switch so as toopen the said circuit including the said control wires, and to therebyde-energize the said windings; means at each of the said stations,operating when the winding of the corresponding relay is de-energized,for retaining the corresponding switch actuated; a second relay at eachof the said stations, each second relay having a winding normallyde-energized and adapted to be connected to the source of power forenergization when the corresponding switch means is actuated; means,controlled by the simultaneous actuation of the said switches, providingenergization of only one of the windings of the said second mentionedrelays; a proceed signal at each station; means controlled by thede-energization of the winding of a rst mentioned relay and theenergization of the corresponding second mentioned relay, to operate thecorresponding proceed signal; a stop signal at each station; and means,controlled by the de-energization of the windings of the correspondingrst and second mentioned relays, to energize the corresponding stopsignal.

5. A block signaling system having a plurality of signal stations andhaving two control wires each extending between at least two stations,the combination therewith including, a source of power at one station;normally closed switch 'means at the said one station connecting one ofthe said control wires to one terminal of the said source of power;normally closed switch means at the other of said stations connectingthe said one control wire to the other control wire; a relay at each ofthe said stations, each relay having a winding normally energized in acircuit including the said switches and the said control wires; controlmeans at each of the said stations, operable while the correspondingwinding is energized, to actuate the corresponding normally closedswitch so as to open the said circuit including the said control wires,and to thereby de-energize the said windings; means at each of the saidstations, operating when the corresponding winding is de-energized, toretain the corresponding switch actuated; signaling means at eachstation operated by the corresponding relay, when the winding of thecorresponding relay is de-energized; and means operable to re-energizethe winding of each of the said relays, to discontinue operation of thesignaling means, as recited.

6. A block signaling system having a plurality of signal stations, theapparatus at one of said stations comprising, a normally open circuitincluding a rst electromagnet; means responsive to the entry of a carinto the block at the said one station, for closing the said circuit soas to energize the said rst electro-magnet; an armature operated by thesaid first electro-magnet; a second electro-magnet and and an armatureoperated thereby; a mechanical latch associated with the armature of therst electro-magnet, and operated by the armature of the said secondelectro-magnet, for retaining the armature of the said rstelectro-magnet in its operated position; a third electro-magnet and anarmature operated thereby; means including contacts of the armatureoperated by the rst electro-magnet in its energized condition, forenergizing the said third electro-magnet; a proceed signal; and meansincluding contacts of the armature operated by the third electro-magnetin its energized condition and contacts of the armature operated by thesecond electro-magnet in its de-energized condition, for operating thesaid proceed signal.

'7. A block signaling system having a plurality of signal stations (I, 2and 3), and having two control line wires (wires 20 'i2-22a; and wire26), each extending between at least two stations (l and 3) thecombination therewith including, a source of power (TL-X) at one station(station l) one of said control line wires (2i), etc.) being connected(via wire 6) to one termi-- nal (T) of the said source of power at thesaid one station (station l), and connected (via jumper wire 24) to theother control line wire (26) at another of said stations (station 3) arelay at each station (Cl and C3), each relay having a winding normallyenergized and connected between the said other control line wire (26)and the other terminal (X) of the said source of power; control means(DI and D3) at each station, each control means operable to open thesaid one control line wire (2i), etc.), and to thereby de-energize thewinding of each relay (Cl and C3) means (Xl and X3) at each station,each means operated by the corresponding relay (Cl and C3), to retainthe corresponding control means (DI and D3) operated, when the windingof the corresponding relay (Cl and C3) is deenergized; a second relay(Ml and M3) at each station, each second relay having a winding normallyde-energized and adapted to be connected to the said source of power (MIvia Dl--l and 9) (23, via Wires 27 and 25) and the other terminal uponthe operation of 'its corresponding control means (DI and D3) a proceedsignal at each station (GI and G3); means (BI-II), operated by thede-energization of the winding of a first mentioned relay (CI)cooperating with means (Hl-l5) o-perated by the energization of thewinding of the corresponding second mentioned relay Ml, for operatingthe said proceed signal;` a stop signal; and means (HI-I3) operated bythe de-energization of the winding of a second mentioned relay (Ml),cooperating with the means (BI-I I) operated by the de-energization ofthe winding of the corresponding first mentioned relay (CI), foroperating the stop signal; and means (Nl and N3) at each station,responsive to a car leaving the block at the corresponding station, forconnecting momentarily the said other control wire (23) to the said oneterminal (T) of the said source of power to re-energize the winding ofeach of the first mentioned relays (Cl and C3).

8. A block signaling system having a plurality of signal stations (I, 2and 3), and having two control line wires (one line wire comprisingwires 23, 22 and 22a, the other line wire comprising wire 23) each linewire extending between at least two stations (I and 3) the combinationtherewith including, a source of power (TL-X) at one station (stationI); one of said control line wires (2li, etc.) including a normallyclosed switch (DI-i9 and D3-23) at each of the said two stations, saidone control line wire being connected (via wire l) to one terminal (T)of the source of power at the said one station, and connected (viajumper wire 2li) to the other control line wire (26) at the other ofsaid two stations (station 3) a relay (CI and C3) at each station, eachrelay having a winding normally energized, and connected between thesaid other control wire (26, via wires 2l and 25) and the other'terminal(X, via wires 28 and Il!) of the source of power at each respectivestation; operating means (AI and A3) at each station, operable while thewinding of the corresponding relay (CI and C3) is energized, to open thecorresponding normally closed switch (Dl-I9 and D3-23), and to therebydeenergize the windings of each of the said relays (Cl and C3) means (XIand X3) at each station operated by the de-energization of the windingof the corresponding relay, for retaining the corresponding normallyclosed switch (DI- I9 and D3-23), open; signaling means at each station(RI-GI and R3-G3); and means (BI-II and B3, etc.) operated by thede-energization of the winding of the corresponding relay (CI and C3),for operating the corresponding signaling means (RI and R3, etc.)

9. A block signaling system having a plurality of signal stations (I, 2and 3), and having two control line wires (one line wire comprisingwires 2B, 22 and 22a, the other line wire comprising wire 23) each linewire extending between at least two stations (I and 3) the combinationtherewith including, a source of power (TMX) at one station (station I);one of said control line wires (2li etc.) including a normally closedswitch (DI-I9 and ID3-23) at each of the said two stations, said onecontrol line wire being connected (Via wire (i) to one terminal (T) ofthe source of power at the said one station, and connected (via jumperwire 24) to the other control line wire (26) at the other of said twostations (station 3) a relay (CI and C3) at each station, each relayhaving a winding normally energized, and connected between the saidother control wire (X, via wires 28 and I0) of the source of power ateach respective station; operating means (AI and A3) at each station,operable while the winding or" the corresponding relay (CI and C3) isenergized, to open the corresponding normally closed switch (Dl- I9 andD3-23), and to thereby deenergize the windings of each of the saidrelays (CI and C3) means (XI and X3) at each station operated by thede-energization of the winding of the corresponding relay, for retainingthe corresponding normally closed switch (DI-I9 and D22-23) open;signaling means at each station (Rl-GI and R3-G3); and means (BI-il andB3 etc.) operated by the de-energization of the winding of thecorresponding relay (Cl and C3), for operating the correspondingsignaling means (RI and R3, etc.); means (Nl and N3) at each station,responsive to a carleaving the block at the corresponding station, forre-energizing the winding of each oi the said relays (Ci and C3) todiscontinue operation of the signaling means.

10. A block signaling system having a. plurality of signal stations (I,2 and-3), and having two control line wires (one line wire comprisingwires 23, 32 and 22a, the other line wire comprising wire 26) each linewire extending between at least two stations (l and 3) the combinationtherewith including, a source of power (T-X) at one station (station I)one of said control line wires (2li etc.) including a normally closedswitch (Dl-i9 and D3-23) at each of the said two stations, said onecontrol line wire being connected (via wire (i) to one terminal (T) ofthe source of power at the said one station, and connected (via jumperwire 2Q) to the'other control line wire (23) at tho other of said twostations (station 3); a relay (CI and C3) at each station, each relayhaving a winding normally energized, and connected between the saidother control wire (25, via wires 2l and 25) and the other terminal (X,via wire:`

38 and I) of the source of oower at each respec--v tive station;operating means (Al and A3) at each station, operable while the windingof the corresponding relay (Ci and C3) is energized, to open thecorresponding normally closed switch (Di-l 3 and DI-23) and to therebyde-energize the windings of each of the said relays (Cl and C3) means(XI and X3) at each station operated by the deenergization of thewinding of the corresponding relay, for retaining the correspondingnormally closed switch (Dl-i3 and Dfi-Q3) open; a second relay (Ml andM3) at each station, each second relay having a winding normallyole-energized and adapted to be connected to the said source of power(MI via Dl-l and wire il) upon the operation of its correspondingoperating means (AI and A3) means controlled by the operation of thesaid normally closed switches pro viding for energization of only one ofthe windings of the said second relays (Ml and M3), when both of thesaid normally closed swit es are operated; a proceed signal (Gi and ateach station; means (BI-l i), operated by the de-energization of thewinding of a first mentioned relay (Cl) cooperating with means (HI-I5)operated by the energization of the winding of the corresponding secondrelay (Ml) for operating the corresponding proceed signal 1l. A blocksignaling system having a plurality of lsignal stations (l, 2 and 3),the apparatus at one of said stations (station l) comprising, a normallyopen circuit (comprising wires 2, 3 and 5) including aiirst-electro-magnet (AI), an armature (DI) for the rst electro-magnet(A|); means (SI responsive to the entry of a car into the block at thesaid one station, for closing the said circuit so as to energize thesaid first electromagnet, and thereby operate the said armature (DI) ofthe first electro-magnet; a second electro-magnet (CI) normallyenergized; an armature (BI) for the said electro-magnet normallyretained in its operated condition by the second electro-magnet; means(Xl) for retaining the said armature (DI) of the first electro-magnet inits operated condition, the said retaining means (XI) being controlledby the said armature (BI) of the said second electro-magnet (Ci); andmeans (DI-I9), responsive to the operation of the said armature (DI) ofthe said rst electromagnet, for de-energizing the said secondelectro-magnet (Cl), and thereby operate the said retaining means (Xi)so as to retain the said armature (DE) of the rst electro-magnet in itsoperated condition; a proceed signal (G|); and means, responsive to theoperated condition of the said armature (DI) of the firstelectro-magnet, cooperating with means (BI-l i responsive to thenon-operated condition of the said armature (Bl) of the secondelectro-magnet, for operating the said proceed signal (Gl).

12. A block signaling system having a plurality of signal stations (I, 2and 3), the apparatus at one of said stations (station i) comprising, anormally open circuit (comprising wires 2, 3 and 5) including a rstelectro-magnet (Al); an armature (DI) for the rst electro-magnet (AI)means (Si) responsive to the entry of a car into the block at the saidone station, for closing the said circuit so as to energize the said rstelectro-magnet, and thereby operate the said armature (Dl) of the rstelectro-magnet; a second electro-magnet (Cl). normally energized; anarmature (Bl) for the said electro-magnet normally retained in itsoperated condition by the second electro-magnet; means (XI) forretaining the said armature (Dl) of the first electro-magnet in itsoperated condition, the said retaining means (XI) being controlled bythe said armature (Bl) of the said second electromagnet (Ci); and means(Dl-I9), responsive to the operation of the said armature (DI) of thesaid first electro-magnet, for de-energizing the said secondelectro-magnet (Cl and thereby operate the said retaining means (Xl) soas to retain the said armature (DI) of the rst electro-magnet in itsoperated condition; a proceed signal (Gl); and means, responsive to theoperated condition of the said armature (DI) of the firstelectro-magnet, cooperating with means (Bl-l I) responsive to thenon-operated condition of the said armature (BI) of the secondelectro-magnet, for operating the said proceed signal (GI); and means,(N I) responsive to the car leaving the block at the said one station,for re-energizing the said second electro-magnet (CI and to therebyrelease the retaining means (Xl) and restore the said armature (DI) ofthe said first electro-magnet to its non-operated condition.

13. A block signaling system having a plurality of signal stationshaving similar apparatus, the apparatus at one station comprising, anormally open circuit including a rst electromagnet; an armature for thefirst electro-magnet; means responsive to the entry of a car into theblock at the said one station, for closing the said circuit so as toenergize the first electro-magnet, and thereby operate the said armatureof the rst electro-magnet; a second electro-magnet normally energized;an armature for the said second electro-magnet normally retained in itsoperated condition by the said second electro-magnet; a mechanicallatch, controlled by the armature of the said second electro-magnet, forretaining the armature of the rst mentioned electro-magnet in itsoperated condition, when the said second electro-magnet is de-energized;a third electro-magnet normally de-energized; an armature for the saidthird electro-magnet normally in a non-operated condition; stop andproceed signals controlled by the armature of the third electro-magnet;means responsive to the operation of the armature of the said rstelectro-magnet, for de-energizing the said second electro-magnet, andthereby release the armature of the said second electro-magnet tooperate latch so as to retain the armature of the rst electro-magnet inits operated condition; means, responsive to the operated condition ofthe armature of the first electro-magnet, for energizing the said thirdelectro-magnet and to thereby operate the armature of the thirdelectro-magnet; means, responsive to the releasing of the armature ofthe second electro-magnet, cooperating with means responsive to theoperation of the armature of the third electro-magnet, for operating thesaid proceed signal; and means, responsive to the non-operated conditionof the armature of the said third electro-magnet, cooperating with thesaid means responsive to the releasing of the armature of the secondelectromagnet for operating the said stop signal.

14. A railway block signaling system for a plurality of separatedstations having, in cornbination, a source of power; anormally-energized relay at each station, each relay having anormally-energized relay-coil; a normally-closed line-circuit includingthe relay-coil at each station and the source of power for retaining therelay-coil at each station normally-energized; a normally-closed switchat each station, each switch included in the said circuit including allof the said relay-coils and operable to open the said circuit forde-energizing all of the said relay-coils; control means at each stationfor operating the corresponding switch to open the said circuit; meansat each station, operated by the de-energization of the correspondingrelaycoil, for retaining the corresponding switch means open; signalingmeans at each station; and means at each station, operated by thede-energization of the corresponding relay-coil, for operating thecorresponding signaling means.

15, A railway block signaling system for a plurality of separatedstations having, in combination, a source of power; a rst lineconnection extending to each station; a normally-energizedelectro-magnet at each station, each magnet having one terminalconnected to the first line connection and its other terminal connectedto one terminal of the source of power; a normally closed switch at eachstation; a second line connection connecting the said first lineconnection to the other terminal of the source of power, the said secondline connection including the normally closed switch at each stationconnected in series therewith; control means at each station operable toopen the corresponding normally closed switch, for disconnecting thefirst line connection from the said other terminal of the source ofpower, and thereby to de-energize the electromagnet at each station;means at each station, operating in response to the de-energization ofthe corresponding electro-magnet, for retaining the corresponding switchmeans open; signaling means at each station; and means at each station,operating'in response to the de-energization of the correspondingelectro-magnet, for displaying the corresponding signaling means.

16.` A railway block signaling system for a plurality of separatedstations having, in combination, a source oi power; a first lineconnection extending to each station; a normally-energizedelectro-magnet at each station, each magnet having one terminalconnected to the iirst line connection and its other terminal connectedto one terminal of the source of power; a normally closed switch at eachstation; a second line connection connecting the said first lineconnection to the other terminal of the source of power, the said secondline connection including the normally closed switch at each stationconnected in series therewith; control means at each station operable toopen the corresponding normally closed switch, for disconnecting the rstline connection from the said other terminal of the source of power, andthereby to de-energize the electro-magnet at each station; means at eachstation, operating in response to the de-energization of thecorresponding electro-magnet, for retaining the corresponding switchmeans open; a normally-open switch at each station, closed by theoperation of the corresponding control means; a proceed signal at eachstation; means at each station, controlled by the closing of thecorresponding normallyopen switch, for displaying the correspondingproceed signal; a stop signal at each station; and means at eachstation, controlled by the cie-energization of the correspondingvelectromagnet, for displaying the corresponding stop signal.

i7. A railway block signaling system for a plurality of separatedstations having, incombination, a source of power; a rst line connectionextending to each station; a normally-energized electro-magnet at eachstation, each magnet having one terminal connected to the rst lineconnection and its other terminal connected to one terminal of the4source of power; a normally closed switch at each station; a secondline connection' connecting the said first line connection to the otherterminal of the source of power, the said second line connectionincluding the normally closed switch at each station connected in seriestherewith; control means at each station operable to open thecorresponding normally closed switch, for disconnecting the first lineconnection from the said other terminal of the source of power, andthereby to de-energiZe the electro-magnet at each station; means at eachstation, operating in response to the deenergization of thecorresponding electro-magnet, for retaining the corresponding switchmeans open; a stop signal at each station; means at each stationoperating in response to the deenergization of the correspondingelectro-magnet, for displaying the corresponding stop signal; a proceedsignal at each station; a normally-open switch at each station, closedby the operation of the corresponding control means; means at eachstation, controlled by the closing of the corresponding normally-openswitch, for displaying the corresponding proceed signal; and meanscontrolled by the opening of the said normallyclosed switches providingfor the display of only one of the said proceed signals, when more thanone of the said normally-open switches are closed. 18. A railway blocksignaling system for a plurality of separated stations, having incombination, a source of power; signaling means at each of saidstations; a control relay at each station; means at each station,controlled by the corresponding control relay, for operating thecorresponding signal; a normally-closed switch at each station; a rstline connection extending to each station; a normally-energizedoperating-coil for each control relay, each coil having one terminalconnected to the said rst line connection and its other terminalconnected to one terminal of the said source ci power; a second lineconnection connecting the said first line connection to the otherterminal of the said source of power, the said second line connectionincluding the normally-closed switch at each station connected in seriestherewith; control means at each station operable to open thecorresponding normally-closed switch, for opening the said second lineconnection, and thereby deenergize each of the operating coils of thesaid control relays; and means at each station, operating in response tothe de-energization of the corresponding relay coil, for retaining thecorresponding normally closed switch opened.

FRANK H. RICHTERKESSING.

